Three professional climbers who were caught in an avalanche at Canada's Banff National Park Wednesday were confirmed dead on Sunday, officials said .

"A party of three mountaineers attempting the east face of Howse Peak in the Icefields Parkway were reported overdue. Parks Canada responded immediately," a spokesperson for Parks Canada said in a statement. "Based on an initial assessment of the scene, it was concluded that all three members of the party were deceased."

David Lama and Hansjrg Auer of Austria and Jess Roskelley of the US were hiking up Howse Peak when an avalanche hit. Howse Peak is the tallest mountain in the Waputik Mountain range.

In a statement, Parks Canada said that the trail "is remote and an exceptionally difficult objective, with mixed rock and ice routes" adding that it requires "advanced alpine mountaineering skills."

As members of The North Face's Global Athlete Team, the three men were considered some of the best climbers in the world.

The spokesperson for Parks Canada described them as "professional mountain athletes and highly experienced."

Lama, 38, was an adept climber. He made the first solo climb of Cerro Torre in Patagonia, Maine Public noted.

Auer, 35, was regarded as "one of the world's top solo climbers," according to Outside . In 2007, he free soloed "The Fish" route on the Marmolada mountain in Italy.

Roskelley, 36, was called "one of America's boldest alpinists" by Men's Journal . When he was 20, he became the youngest person to summit Mount Everest at the time. He scaled the mountain with his father and fellow mountaineer John Roskelley, per NPR .

On Wednesday, search and rescue missions were unable to be conducted due to avalanche conditions. Per CNN , officials believe it was a size 3 avalanche.

At the time, the climbers had been presumed dead.

On Sunday, Banff National Park confirmed on Twitter that the men had been confirmed dead.

"We extend our sincerest condolences to the families, friends and loved ones of the mountaineers," the posts on Twitter said. "We would also like to acknowledge the impact that this incident has had on the tightknit, local and international climbing communities."

The tweets also acknowledged the search and rescue efforts.

"All three of them, they had in common this similar goal of going and doing remote climbs on big mountains in a very pure, alpine way," Brandon Pullan, the editor in chief of Gripped magazine, told the CBC .